“I am sad to report that a two-year-old miniature horse from Griswold tested positive for the disease,” said Commissioner Reviczky. “This case underscores the importance of vaccinating horses to protect them from mosquito-transmitted diseases.”

According to agency officials, the horse’s owner noticed the animal was sick on September 8, 2013, appearing dull and having a poor appetite. The miniature horse developed a fever, became progressively more depressed and uncoordinated, and continued to deteriorate despite treatment. The attending veterinarian humanely euthanized the animal.

Diagnostic samples were collected at the Connecticut Veterinary Medical Diagnostic Laboratory at the University of Connecticut in Storrs and were submitted to the United States Department of Agriculture (USDA) National Veterinary Services Laboratories, where they tested positive for EEE.

The miniature horse had no documented history of EEE or West Nile Virus (WNV) vaccinations and had not traveled recently. Positive EEE mosquitoes have been reported by the Connecticut Mosquito Management Program (www.ct.gov/mosquito) in the area several times since July.

“Horse owners should review vaccination records with their veterinarians to ensure that EEE and WNV vaccinations are current and to take precautions against mosquito bites, especially when residing in areas with known infected mosquitoes” said Dr. Mary Jane Lis, State Veterinarian for the Connecticut Department of Agriculture. The mortality rate of EEE infected horses showing clinical signs is 75-90%. Surviving horses have a high incidence of residual neurologic deficits.

Neurological diseases of domestic animals, such as EEE and WNV, are reportable to the State Veterinarian. As of September 10, 2013, officials in 16 states have reported 123 EEE cases involving horses.

More information about EEE is available on USDA’s website and on the United States Geological Survey’s website.